Tiny embedded grains. Specks. Inclusions

[Dave Burbank]

I'm noticing that most of the tiny spots that come into FOV below the surface are mostly in movies 4200 through 4400, with a few in bordering movies.

If the movies are listed to match the order they were arranged in space (and manufactured?) this is a rather small and specific area for tracks to be found.

Because these tracks are so small (low velocity?), and for the reasons above I am going to take a shot in the dark and guess that either there are minor manufacturing defects in the aerogel in ths region, or some debris from the probe struck the aerogel here at relatively slow speeds. I have absolutely no training in this field, so I could be completely wrong, I'm just guessing because of the pattern I'm seeing.

Take a look at your events and let me know if any of you notice anything similar.

[Sasari]

I noticed the same thing. From this thread it sounds thay may be inclusions in the gel


http://stardustathome.ssl.berkeley.edu/ ... .php?t=504

[geckzilla]

I'm starting to think I might be marking too many of these movies.

Here's my list so far:
http://www.geckzilla.com/myevents/myevents.php.htm

Except for the very first one there is an inclusion in all of those. (First one was from when I was just starting out, newbie mistake)

Some are very very tiny, maybe only 2 pixels and only visible in 3 frames. Some might not even be in focus yet but only beginning to come in focus before the movie ends.

I'm thinking I might be a little trigger happy here but so far the only thing I've found on inclusions is "click them just in case." so I've been doing exactly that. However, even the smallest, hardest to see calibration movies don't look like any of these.

Key identifiers of inclusions:
Grouped specs (there are multiples on one screen more often than not)
No visible hollow trail.

Should I keep marking them or what? Thoughts?

[DustBuster]

I have not been marking them anymore, but writing down the movie number.

[geckzilla]

I'm curious. Why write down the numbers? In case they need them later or just for your own purposes?

[Kalman]

Hi!

As I have browsed your candidate movies, I've noticed a kind of object again and again. They don't look like a classic track on calibration images, but they are definitely below the surface of aerogel. I call them tiny embedded grains (TEG's, hmmm?), but I recognized that many others walk into them and usually we are in doubt if they are real tracks. Consider the topics below:

http://stardustathome.ssl.berkeley.edu/ ... .php?t=407
http://stardustathome.ssl.berkeley.edu/ ... .php?t=709

Anyway, they seem to be a sort of object that we often find, so I think they claim some attention. Here are the characteristics as I see:

-small in size ( < 3 microns)
-have embedded 10-30 slides below surface (or still deeper, but I cannot check)
-seem to be local (there is a specific depth where they are in focus)
-often several one appear in a movie (there are 8 on movie 44387!)
-the surface looks smooth above them

Below is a collection of samples. The first two I found myself, others are findings of forum members (sorry for not mentioning names):

http://stardustathome.ssl.berkeley.edu/ ... e_id=44387
http://stardustathome.ssl.berkeley.edu/ ... e_id=42055
http://stardustathome.ssl.berkeley.edu/ ... e_id=47027
http://stardustathome.ssl.berkeley.edu/ ... e_id=41661
http://stardustathome.ssl.berkeley.edu/ ... e_id=44976
http://stardustathome.ssl.berkeley.edu/ ... e_id=41411
http://stardustathome.ssl.berkeley.edu/ ... e_id=43161
http://stardustathome.ssl.berkeley.edu/ ... e_id=42453
http://stardustathome.ssl.berkeley.edu/ ... e_id=44255
http://stardustathome.ssl.berkeley.edu/ ... e_id=43353
http://stardustathome.ssl.berkeley.edu/ ... e_id=43270
http://stardustathome.ssl.berkeley.edu/ ... e_id=42078
http://stardustathome.ssl.berkeley.edu/ ... e_id=41726
http://stardustathome.ssl.berkeley.edu/ ... e_id=43468
http://stardustathome.ssl.berkeley.edu/ ... e_id=41806

Now, they may be whatever, but I have a few tips:

a) large, slow and compact dust particles that slow down shortly in aerogel (hopefully )
b) earthly dust that had fallen into the gel in production time
c) some impurity or bubbles in the gel material
or they are just that we are looking for?

What do you think? I guess we can't find it out until they extract some of that grains.
But I hope there is something from space. This hunt is a great fun! I just feel I participate in edge science

[KarMann]

c)

[Kalman]

Some addition:
It is reasonable that researchers don't have a clear idea about how must be a track look like.
But they should have some experience on the possible impurity of the aerogel, because it can be well studied on earth.
Still there is not any warning in the tutorial like "be aware of little black spots".

[oscar]

I have also seen the little spots, sometimes in small clusters of 3 or 4. I have ID'd the spots as possible dust although the spots do not look like tracks.

[DustBuster]

The topic has been raised all over the forum since they started being discovered (and notice they seem to be primarily in the 4XXXXX series). There has been much speculation and debate on the forum as to what they are. The movies like this that I have seen posted in the forums seem to fall into two main categories:

a) something suspended in the gel; with no visible point of entry/track.
b) something suspended in the gel; with a faint ring that shows up (which may turn out to be due to focus artifacts).

There have been no postings that the Stardust team has confirmed any candidates at this point and so we still don't have a good handle on what we are looking for and we are clicking these and other things that look interesting.
My personal (untrained) thoughts were that some of these met the criteria of a track layed out in the tutorial, but they were extrememly smaller than I had expected.
In addition, multiple "dots" started showing up in a single movie and after I considered the number of expected particles to be found, it was my supposition that these might not be tracks- but more than likely (elsewhere described) "inclusions" (akin to artifacts resulting from manufacture).
Since there have already been a number of these that have been flagged and will be looked at, I didn't want to add to the pile. But I am writing them down for my own reference in case they are discovered to be something of interest so I may forward the information to the team.
I'm not saying you should or should not click on them; it is your judgement call- and until there is some official word we just don't know. I may be missing out on being the first to discover a particle, or we all might be "trigger" happy- but neither has been deemed right or wrong yet.

[icebike]

I have not been marking them anymore, but writing down the movie number.

Any possibility of getting a definitive word out of the project scientists?

Lots of people are still marking them - especially when its more than a couple pixels, or just one per movie.

I don't expect the scientists to drop everything to answer this, but it would seem that with a few minutes of their time they could head off a lot of false positives and save hours an hours of volunteers time stareing into the gray looking for tiny specs.

[geckzilla]

I'm staring at one right now. To click, or not to click? That is the question.

Edit: Okay, I'm not clicking them, and I'm not writing down numbers either. On a completely unrelated note I am happy to see two decimal places now. Bye-bye 100% round-up.

[Kalman]

In addition, multiple "dots" started showing up in a single movie and after I considered the number of expected particles to be found, it was my supposition that these might not be tracks- but more than likely (elsewhere described) "inclusions"
...
Since there have already been a number of these that have been flagged and will be looked at, I didn't want to add to the pile. But I am writing them down for my own reference in case they are discovered to be something of interest so I may forward the information to the team.

These are rational words. I join to them. However it would be nice to get some advice from the team, because it looks like many new volunteers comes through this click-or-not-to-click period.

[beef1020]

I ran accross a calibration movie with the small specks appearing below the surface which a lot of people have been marking as tracks. When I clicked on the specks I got the movie wrong!!! The number of the movie is as follows:

4094685V1

The 'tracks' I clicked are on the bottom right side of the picture.

[geckzilla]

Unfortunately, you can't link to calibration movies by any means. So we can't really see what you are talking about.